[PATCH] clk: sp7021: fix infrastructure clocks clobbering PLL provider entries
Andrew Gaylard <[email protected]>
| Newsgroups | org.kernel.vger.linux-clk,org.infradead.lists.linux-arm-kernel |
|---|---|
| Message-ID | <[email protected]> |
The sp_clk_gates[] array previously included 9 infrastructure gate clocks (CLK_SYSTEM, CLK_IOCTL, etc.) appended after the 64 DT-visible gate clocks. The registration loop used the array index directly as the hws[] index, so infrastructure clocks at positions 64-72 overwrote hws[PLL_A] through hws[PLL_SYS]. As a result, DT lookups for <&clkc PLL_E_25> (index 67), PLL_E_2P5 (66) and PLL_E_112P5 (68) silently resolved to CLK_RBUS, CLK_IOP and CLK_SDCTRL0 respectively. The L2SW Ethernet driver believed it was holding the PLLE outputs, but was actually double-referencing already- critical infrastructure clocks. The real PLLE outputs remained at enable_count=0 and were powered down by clk_disable_unused(), causing an Ethernet hang on boards with fixed-link MAC-to-MAC connections. Fix by splitting infrastructure clocks into a separate sp_clk_infra[] array and registering them with a dedicated loop that uses a local hw variable rather than an hws[] slot. Since these clocks have no DT consumer they do not need to appear in the of_clk provider table. With the provider table correct, the L2SW driver's devm_clk_get_enabled() calls now hold the actual PLLE outputs, making CLK_IS_CRITICAL on plle and its sub-outputs unnecessary. Remove it. Signed-off-by: Andrew Gaylard <[email protected]> --- drivers/clk/clk-sp7021.c | 42 +++++++++++++++++++++++++++++----------- 1 file changed, 31 insertions(+), 11 deletions(-) diff --git a/drivers/clk/clk-sp7021.c b/drivers/clk/clk-sp7021.c index 1d067b0af8a7..50c667cbb3dc 100644 --- a/drivers/clk/clk-sp7021.c +++ b/drivers/clk/clk-sp7021.c @@ -124,9 +124,14 @@ static const struct sp_clk_gate_info sp_clk_gates[] = { { 0x97 }, { 0x98 }, /* CLK_ICM: Input Capture Module */ { 0x99, 0, true }, /* CLK_AXI_GLOBAL: AXI interconnect, no driver consumer */ - /* Infrastructure clocks: all default to enabled in hardware but - * have no driver consumer, so marked critical to prevent gating. - */ +}; + +/* + * Infrastructure clocks have no DT consumer so are not exposed + * through the of_clk provider. They are registered separately and + * marked CLK_IS_CRITICAL so clk_disable_unused() never gates them. + */ +static const struct sp_clk_gate_info sp_clk_infra[] = { { 0x00, 0, true }, /* CLK_SYSTEM: SYSTEM CLKEN mo_clken0 bit 0 */ { 0x03, 0, true }, /* CLK_IOCTL: IOCTL CLKEN mo_clken0 bit 3 */ { 0x04, 0, true }, /* CLK_IOP: IOP CLKEN mo_clken0 bit 4 */ @@ -644,25 +649,23 @@ static int sp7021_clk_probe(struct platform_device *pdev) /* * PLLE and all its sub-outputs are used by the L2SW Ethernet switch * (50MHz RMII, 25MHz MII/100M, 2.5MHz MII/10M, 112.5MHz MAC fabric). - * The L2SW driver explicitly claims these via clock-names in DTS, but - * CLK_IS_CRITICAL is kept as a belt-and-suspenders guard in case the - * driver consumer reference isn't sufficient on all board configurations. + * The L2SW driver explicitly claims these via clock-names in DTS. */ hws[PLL_E] = sp_pll_register(dev, "plle", &pd_ext, PLLE_CTL, - 6, 2, 50000000, 0, 0, CLK_IS_CRITICAL); + 6, 2, 50000000, 0, 0, 0); if (IS_ERR(hws[PLL_E])) return PTR_ERR(hws[PLL_E]); pd_e.hw = hws[PLL_E]; hws[PLL_E_2P5] = sp_pll_register(dev, "plle_2p5", &pd_e, PLLE_CTL, - 13, -1, 2500000, 0, 0, CLK_IS_CRITICAL); + 13, -1, 2500000, 0, 0, 0); if (IS_ERR(hws[PLL_E_2P5])) return PTR_ERR(hws[PLL_E_2P5]); hws[PLL_E_25] = sp_pll_register(dev, "plle_25", &pd_e, PLLE_CTL, - 12, -1, 25000000, 0, 0, CLK_IS_CRITICAL); + 12, -1, 25000000, 0, 0, 0); if (IS_ERR(hws[PLL_E_25])) return PTR_ERR(hws[PLL_E_25]); hws[PLL_E_112P5] = sp_pll_register(dev, "plle_112p5", &pd_e, PLLE_CTL, - 11, -1, 112500000, 0, 0, CLK_IS_CRITICAL); + 11, -1, 112500000, 0, 0, 0); if (IS_ERR(hws[PLL_E_112P5])) return PTR_ERR(hws[PLL_E_112P5]); @@ -689,7 +692,7 @@ static int sp7021_clk_probe(struct platform_device *pdev) return PTR_ERR(hws[PLL_SYS]); pd_sys.hw = hws[PLL_SYS]; - /* gates */ + /* gates, directly mapped into hws[] for DT lookup */ for (i = 0; i < ARRAY_SIZE(sp_clk_gates); i++) { char name[10]; u32 j = sp_clk_gates[i].reg; @@ -706,6 +709,23 @@ static int sp7021_clk_probe(struct platform_device *pdev) return PTR_ERR(hws[i]); } + /* infrastructure gates, not in hws[] */ + for (i = 0; i < ARRAY_SIZE(sp_clk_infra); i++) { + char name[14]; + u32 j = sp_clk_infra[i].reg; + struct clk_hw *hw; + + sprintf(name, "infra_0x%02x", j); + hw = devm_clk_hw_register_gate_parent_data(dev, name, &pd_sys, + CLK_IS_CRITICAL, + clk_base + (j >> 4) * 4, + j & 0x0f, + CLK_GATE_HIWORD_MASK, + NULL); + if (IS_ERR(hw)) + return PTR_ERR(hw); + } + return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clk_data); } -- 2.53.0